BASAL METABOLISM. 



69 



TABLE 21. Basal metabolism of A. H. M., 9 a. m. to 6 p. m., December 3 and 4, 1906. 



In the 24-hour experiments thus far considered, the base-line was 

 determined immediately prior to the ingestion of the food. In the 24- 

 hour experiment with the subject A. H. M., February 2 to 3, 1906, in 

 which crackers and milk were taken, such basal values were not avail- 

 able. A base-line obtained in an experiment on November 21 to 23, 



1905, was therefore used, this being the nearest date on which a fasting 

 value was obtained for this subject. Although the detailed discussion 

 of the fasting experiment with A. H. M., December 3 to 5, 1906, shows 

 that we have available still another fasting value, it did not seem desir- 

 able to average the two values for a base-line for this particular food 

 experiment, inasmuch as the metabolism of this subject in the fall of 

 1905 was distinctly different from that in the latter part of 1906. 



The results of the food experiment with A. H. M., February 2 to 3, 



1906, are given in table 22, together with the average values for the 

 fasting experiment of November 21 to 23, 1905. The values obtained 

 on the two fasting days agree closely; the average heat production was 

 1,755 calories. With the ingestion of the crackers and milk, which had 

 a total fuel value of about two-thirds of the daily requirement, the heat 

 production was increased 239 calories, with a corresponding increase in 

 the carbon-dioxide production a.nd oxygen consumption. Here again 

 it is extremely difficult to account for the unusually large increment. 

 While it would normally be ascribed solely to the ingestion of the food, 

 it is so at variance with the results obtained in almost all of the other 

 experiments that one must question the reliability of the base-line. 

 This experiment is an admirable illustration of the unsatisfactory use 

 of 24-hour periods, particularly when there is a considerable interval 



